Abstract: The present invention provides a system and a method to reform hydrocarbon fuels, including sulfur-laden liquid fuels, to produce a reformate stream containing hydrogen. The system comprises a reforming reactor using a hydrocarbon stream and a water stream as reactants. The water stream is mixed with a hydrogen-rich stream prior to mixing with the hydrocarbon stream and fed to the reforming reactor, which contains a precious metal based catalyst. In one embodiment of the present invention, the temperature of the catalyst is lower at the inlet to prevent formation of coke by pre-reforming heavy hydrocarbons to methane, and higher at the outlet for efficient production of hydrogen. In another embodiment, air is introduced periodically into the system to burn off any metal sulfides and coke deposits that could form. In another embodiment, pure hydrogen is separated from the reformate stream using a hydrogen selective, sulfur-tolerant membrane or by pressure swing adsorption.